Objective To retrospectively investigate the endoscopic characteristics and pathological features of colorectal polyps in over-aged patients (≥80 years). Methods The 1617 colonoscopies performed between January 2006 and December 2010 were enrolled in our retrospective analysis. The detection rate, size, location, form and pathological feature of polyps in 150 over-aged patients were investigated, and they were compared with those in 832 young patients (＜60 years) and 635 old patients (60-79 years) with colorectal polyps. Results The detection rate of polyps was 62.0% in over-aged group, and was significantly higher than in young group and old group (30.2% and 48.7%, respectively, χ2=56.58 and 8.64,both P＜0.001). The malignant transformation rate of ascending colon polyp was 5.4% in over-aged group, and was significantly higher than in young group (1.2%, χ2=4.90, P＜0.05), but there was no significant difference between over-aged group and old group (3.9%, χ2=0.36, P＞0.05). There were no statistical differences in canceration rate, polyp diameter, morphology and adenomatous polyp rate among the three groups. The malignant transformation rate was significantly increased in adenomatous polyps with diameter over 2 cm, but didn't reach statistical significance. Conclusions The polyp detection rate is noticeably higher in the over-aged than in the old and the middle-aged, and the malignant transformation probability is also increased. The colonoscopy indications in the high risk age groups should appropriately be broadened, they should receive regular intervals follow-up, and undergo polypectomy in time if necessary.

To improve the quality of experimental teaching,investigating the independent design experiments are carrying out in preventive medicine by public health experimental teaching center in our school.We take preventive medicine professional as an example,and besides the classical basis experiments,some experiments are verification project at present,in which students are not strongly interested.On the basis of the integration of the classic experiments,according to the national standard of the experimental method,we are trying to carry out part of the independent design experiments to meet the needs of students learning.The effect of those independent design experiments shows that it is appropriate carrying out independent design experiments on the basis of the existing classical experimental project in preventive medicine experimental teaching,to a certain extent,which will stimulate students' learning interest and enhance their sense of achievement.This study is conducive to the cultivation of medical students' innovation,independent thinking,analysis and problem-solving ability,practical ability and teamwork spirit.

To study the chemical constituents of Alchornea trewioides, silica gel column chromatography, Sephadex LH-20, reverse phase ODS column chromatography, MCI and semi-preparative HPLC were used to separate the 95% EtOH extract of the root of Alchornea trewioides. The structures were elucidated on the basis of spectroscopic studies including ESI-TOF-MS, 1H NMR, 13C NMR, HSQC and HMBC. Eight phenolic acids were obtained and identified as 1-O-galloyl-6-O-vanilloyl-beta-glucose (1), gallic acid (2), ethyl gallate (3), syringic acid (4), glucosyringic acid (5), erigeside C (6), 3, 4-dimethoxyphenyl-(6'-O-alpha-L-rhamnosyl)-beta-D-glucopyranoside (7) and 3, 4, 5-trimethoxyphenyl-(6'-O-galloyl)-O-beta-D-glucopyranoside (8). Among them, compound 1 is a new compound, compounds 4-8 are isolated from the genus Alchornea for the first time, and the others are isolated from the plant for the first time.

To examine whether or not the regulatory sequence of chicken ovalbumin gene can drive transgene expression specifically in hen oviduct, the authors constructed an oviduct-specific expression vector (pOV), containing 3.0 kilobases (kb) of the 5'-flanking sequence and 3.0 kb of the 3'-flanking sequence of the chicken ovalbumin gene. Jellyfish green fluorescence protein (EGFP) reporter gene and bacterial LacZ reporter gene were respectively inserted into the downstream of the 5'-regulatory region.The recombinants were named as pOVEGFP and pOVLacZ. Two transfer systems, in vitro and in vivo, were used to verify the function of the vector. In vitro, the plasmid DNA pOVEGFP and pEGFP-N1 were transfected respectively by the polyethyleneimine procedure into the primary chicken oviduct epithelium (PCOE) and fibroblasts cells isolated from laying hens. In vivo, the recombinant vector pOVLacZ was injected into egg-laying hens via wing vein and the tissues were collected for RT-PCR analysis.The results showed that expression of pEGFP-N1 was achieved at low level in oviduct epithelial cells and at high level in fibroblasts, but that the recombinant vector was not expressed in both cells. RT-PCR analysis showed that the LacZ gene was transcribed in the oviduct, but not in the heart, liver, kidney and spleen of the injected hens. Accordingly, the ?-galactosidase activity was only detected in the oviduct magnum (116.7 mU/ml) and eggs (16.47 mU/ml). These results indicated that the cloned regulation regions of chicken ovalbumin gene could drive exogenous gene expression specifically in the oviducts of hens. In vivo gene injection via wing vein may serve as a rapid production system of recombinant proteins in chicken eggs. In addition, the cultured primary oviduct cells from laying hens were not efficient temporary expression systems for analyzing the function of regulating elements of ovalbumin gene.

To look for a more stable and convenient way of constructing short hairpin RNA expression vectors targeting the latent membrane protein-1(LMP-1) encoded by Epstein-Barr virus(pshLMP1), and to study the inhibition function of pshLMP1 expression vectors in HNE1 cells, we designed the pshLMP1 expression cassette and pshLMP1 expression vectors by both the annealing method and PCR method and then co-transfected with pEGFP-N1-1158 into HNE1 cells to observe the mRNA and protein levels of LMP-1 genes by green fluorescence analysis, RT-PCR and western blot. pshLMP1 expression vectors were successfully obtained by both methods but better cloning efficiency was achieved and fewer deletions and mutations of nucleotides were achieved with the PCR method. Furthermore, the mRNA and protein levels of LMP-1 genes were down-regulated by pshLMP1 expression vectors. According to our research, we found that the PCR method provides a more efficient way to construct pshLMP1 expression vectors which have the ability to inhibit the function of LMP-1 genes expressed in HNE1 cells, and also provides a novel application of RNA interference technology against-EBV.

Objective: To study the role of activating transcription factor 2 (ATF-2) in the growth of mandibular condyle cartilage. Methods: Primary chondrocytes of condyle were cultured. Expression plasmid of ATF-2 and plasmid bcl-2 promoter were transfected into chondrocytes. Luciferase assay and Western blot were used. Results: The absence of ATF-2 in mandibular condyle chondrocytes resulted in a decline in bcl-2 promoter activity, reduction in bcl-2 protein level. Conclusion: The results strongly imply that ATF-2 is required for adequate bcl-2 expression, and play a significant role in controlling growth plate chondrocyte progression.

Objective To analyze the relationship between the clinical features of hepatoblastoma and serum alpha-fetoprotein level.Methods We did a retrospective study in 74 cases into the relationship of clinical stages,treatment,prognosis,and AFP value in hepatoblastoma.Results In Stage Ⅰ and Ⅱ patients,the average AFP was (36 333 ± 13 782) ng/ml and in Stage Ⅲ and Ⅳ,the average AFP was (78 346 ± 27 956) ng/ml,P ＜ 0.05.68 patients received preoperative chemotherapy with alpha-fetoprotein determinations before and after chemotherapy respectively.In 44 cases AFP decreased ＞ 50％ after chemotherapy,and in 20 cases AFP declined ＞90％,while in 13 cases AFP increased after chemotherapy.15 cases had serum AFP measured on the first postoperative day,among them 10 cases had a ＞ 50％ AFP decline,3 cases had a ＜ 50％ AFP decline,while in 2 cases AFP value increased.52 cases were postoperatively followed-up,with overall 3 year-survival rate of 86.5％ ; 7 cases recurred,4 died.The average preop AFP level in 7 recurred cases was (27 060 ± 3 569) ng/ml,while the average preop AFP level in those of 3-year recurrence-free was (29 865 ± 5 867) ng/ml,P ＞ 0.05.Only 57％ tumor recurred cases had back to normal AFP level within one month postop,while 89％ long term survivals reported normal range of AFP during that period,P ＜ 0.05.Conclusions Serum AFP level in patients with hepatoblastoma is related to the course of disease.It can be used to estimate the effect of clinical chemotherapy.The speed of alpha-fetoprotein decline postop can be used as an indicator of prognosis.The postoperative normal AFP level within 4 weeks predicts a favorable prognosis.

Objective To evaluate the effects of different concentrations of chloroprocaine on KCNQ2/Q3 channel currents in HEK2936 cells.Methods Human embryonic kidney (HEK293) cells served as an expression system.KCNQ2 and KCNQ3 cDNAs and green fluorescent protein were transfected into HEK293 cells by using lipofectamine.The KCNQ2/Q3 currents were recorded by using the whole-cell patch-clamp technique.Part Ⅰ The transfected HEK293 cells were randomly divided into 4 groups (n =11 each):control group,and 1,10 and 100 mmol/L chloroprocaine groups.The KCNQ2/Q3 channel currents produced by different concentrations of chloroprocaine were recorded under different holding potentials (-40,0 and 40 mV) and the action time was 1 min.Part Ⅱ The transfected HEK293 cells were randomly divided into 2 groups (n =5 each):control group and 10 mmol/L chloroprocaine.The KCNQ2/Q3 channel currents were recorded under different holding potentials (-80-30 mV)and the action time was 1 min.Different test potentials were normalized and fitted to Boltzmann function,and KCNQ2/Q3 channel Ⅰ-Ⅴ curve was then obtained.The activation and deactivation currents were both fitted to a single exponential function and the time constants for current activation and for current deactivation were calculated.Results Part Ⅰ When the holding potential was 40,0 and-40 mV,the suppression rate of KCNQ2/Q3 channel currents in HEK293 cells was higher in 1,10 and 100 mmol/L chloroprocaine groups than in control group (P ＜0.05 or 0.01).Part Ⅱ Compared with control group,the time constant for the current activation at 0 mV of holding potential was prolonged,the time constant for the current deactivation was shortened when the holding potential was-80 mV,and the half-activation voltage of KCNQ2/Q3 channels was increased,the activation curve shifted to the depolarized potentials,and KCNQ2/Q3 channel Ⅰ-Ⅴ curve slope was decreased in 10 mmol/L chloroprocaine group (P ＜ 0.05).Conclusion Chloroprocaine concentration-dependently suppresses KCNQ2/Q3 channel currents in HEK2936 cells.The KCNQ2/Q3 channel is closed in advance due to KCNQ2/Q3 channel opening delay induced by chloroprocaine thus decreasing the activity of KCNQ2/Q3 channels.

Objective To analyze the clinical manifestations,diagnosis and treatment of cerebral amyloid angiopathy (CAA) associated intracerebral hemorrhage.Methods The clinical manifestations,treatment and prognosis of CAA associated intracerebral hemorrhage were analyzed in 4 patients who were identified as CAA-related hemorrhage (CAAH) by pathology.Results All of the 4 patients showed massive lobar intracranial hemorrhage,and underwent craniotomy evacuation of hematoma.One patient had postoperative hemorrhage,and 2 patients were treated with recombinant activated factor Ⅶ after operation.In the next 6 months,re-hemorrhage was found in 3 patients in whom one patient died due to massive hemorrhage.Conclusions CAAH has varied clinical manifestations with high risk of cerebral hemorrhage,and pathological diagnosis is necessary for a definite diagnosis.The very elderly patients with CAAH can benefit from the craniotomy evacuation of hematoma.Although surgery for massive hemorrhage has risks in very elderly patients,it is a better treatment to save their lives.

Objective:To investigate the effects of corticotomy assisted orthodontic treatment for mild skeletal Class Ⅱ malocclusion. Methods:7 adult patients with mild skeletal Class Ⅱ division 1 malocclusion were included and underwent corticotomy assisted ortho-dontic treatments.3D measurements and analysis of CBCT data before and after treatment were conducted.Results:The average dura-tion of upper anterior teeth retraction was 3.2 months.After treatment,obvious retraction of up incisiors with the retraction of maxillary alveolar bone and the upper lip backward and downward movement were observed.Conclusion:Corticotomy assisted orthodontic treat-ment is effective in the treatment of mild skeletal Class Ⅱ malocclusion by the retraction of uper anterior teeth,alveolarar bone and soft-tissue profile improvement.